Seeds and plantlets are individually planted in a soil medium and housed in a greenhouse for germination and hardening. During this process, the seeds or plantlets are planted in a soil medium contained in small plastic liners which are placed in a flat. These flats are then stored in the greenhouse, often on wooden supports such as tables or benches on the greenhouse floor. The plantlets are typically placed side by side at a common elevation in the greenhouse to form a mat of plants extending across the greenhouse on a common plane. By placing the plantlets together as described in the prior art, the plantlets tend to reduce the light that is available to adjacent plants and also cause dead air spaces adjacent the plants, thus inhibiting growth. Further, the liners, flats or pots are opaque and therefore do not transmit any available light therethrough.
A further disadvantage of prior art systems is that the liners must be manually moved from one location to another. In particular, to remove plantlets from the liners, the liners either need to be removed from the greenhouse or the laborer must work at the location of the liner.
Other objects and advantages of the invention will appear from the following description.